Open defects

Etch Profiles. The final profile of a wet etch can be strongly influenced by the crystalline orientation of the semiconductor sample. Many wet etches have different etch rates for various exposed crystal planes. In contrast, several etches are available for specific materials which show Httle dependence on the crystal plane, resulting in a nearly perfect isotropic profile. The different profiles that can be achieved in GaAs etching, as well as InP-based materials, have been discussed (130—132). Similar behavior can be expected for other crystalline semiconductors. It can be important to control the etch profile if a subsequent metallisation step has to pass over the etched step. For reflable metal step coverage it is desirable to have a sloped etched step or at worst a vertical profile. If the profile is re-entrant (concave) then it is possible to have a break in the metal film, causing an open defect. 

To provide the best possible testing of ampoule tightness with fast poststerilization vacuum. This testing method (presented above) achieves maximum effectiveness when the open defects of the ampoules are below the level of the solution. Ampoule rotation is the ideal method for achieving this condition regardless of the location of the defect on the ampoule (tip, shoulder, bottom). 

C Plugged Improved C veneer with splits limited to 3.2 mm width and knotholes or other open defects limited to 6.4 x 12.7 mm. Wood or synthetic repairs permitted. Admits some broken grain. 

Moreover, bare metal under delaminated coating regions may not be detected under all circumstances, especially if the coating resistivity over the delaminated area and dielectric constant are identical to those in regions where the coating is not delaminated. The hypothetical relationship between and open defect area is shown in Fig. 13 [752]. No ASTM standard currently exists for conducting impedance measurements on coated metals. 

During evaluation, the defect manager determines the difficulty of the fix, the risk involved and the amount of time necessary to make and test the fix. If a defect is set to onHold, the reason/justification to accept the open defect in the released version will be documented. 

In order to release a product - and all its updates - for clinical use, it is mandatory to re-evaluate all the open defects for their level of risk none with severe safety risks can be left open, all those remaining have to be formally evaluated and accepted, documenting the reasons for the acceptance and/or the workaround to be applied. The formal defect disposition is the last step of the validation process and an input to release process. Defect list, risk evaluation, disposition and justification are part of the validation records. In special cases a version can be approved for release if the validation documents are not formally completed in no case can a version be approved if the risk evaluation is not completed. 

Aluminum oxides and related compounds have long been technologically important as abrasives (corundum) and in refractories and ceramics in the a-crystalline modification. In the y modification, a more open, defect structure, aluminum oxide becomes activated alumina and is useful in chromatography and in catalysis. A third modification occurs on the surface of the metal on exposure to air and serves as the well-known protective oxide. A more recent technological achievement is the production of remarkably uniform cylindrical fibers of AI2O3. These fibers can be incorporated in a variety of fabrics, papers, ropes, and so on, which gain the advantage of stability to very... 

Another deeply investigated system is that of Ti-MFI (or Ti silicalite) [255]. Only a very small amount of Ti actually enters the silicalite structure in normal tetrahedral sites, although some of them can be bonded to hydroxy groups in open defects [256]. Anatase-like extraframework Ti oxide particles are formed when excess titanium is present upon the preparation. The presence of Ti makes Ti-silicalite less defective than pure silicalite and also changes its room temperature structure from monoclinic to orthorombic. A recent neutron diffraction study showed that Ti sitting is preferential on the sites where defects are frequently present in pure silicalite [257]. 

Absence of any visible bladder can reveal either cloa-cal or bladder exstrophy. In both malformations, which may present with omphalocele (Grignon and Dubois 1999), there is an open defect of the abdominal or perineal wall. Widening of the distance between pubic bone echoes can be shown by prenatal sonography. This finding (Fig. 6.1) can also be shown in epispadias, the third and less severe malformation in this spectrum. 

The model for anodic undermining shows large similarities to cathodic delamination. The main difference is the fact that oxygen transport through an open defect or... 

Fuel leakages are qualitatively indicated by a sudden increase in the concentrations (spiking) of fission products, especially noble gases and iodine nuclides. The appearance of less volatile nuclides in the coolant (e.g., transuranium nuclides) suggests the occurrence of open defects. 

Two major types of defect can be distinguished without the need to define their sizes exactly tight and open. Tight defects allow mostly volatile fission products to migrate into the coolant after some retention, while open defects also permit the release of fuel fragments into the water. Two release mechanisms can be distinguished ... 

Releases from open defects are characterised by a low concentration ratio of to assuming the relatively free leakage of aU iodine nuclides. 

There are fuel elements with open defects in the core if... 

For a long time, the wheels were mainly tested with dye penetration. This test procedure can make defects which are open to the surface of the material visible for the tester. It is, however, common knowledge that the test results vary greatly depending on the subjective view of the individual tester. 

Fig. 2 shows the CFRP-sandwich specimen and the transducer mounted on the scanner. Fig. 23 presents a C-scan of the specimen as first interesting result. Only the defects visible from the outside are indicated. The distance between transducer and specimen was smaller than the focal length, so that the angle of incidence at the edge of the sound beam converts the longitudinal waves to Rayleigh-waves in the specimen. These waves provide a very sharp image of the surface. This method opens the possibility for a non-contact acoustic microscope. 

Radiative recombination of minority carriers is tlie most likely process in direct gap semiconductors. Since tlie carriers at tlie CB minimum and tlie VB maximum have tlie same momentum, very fast recombination can occur. The radiative recombination lifetimes in direct semiconductors are tlius very short, of tlie order of tlie ns. The presence of deep-level defects opens up a non-radiative recombination patli and furtlier shortens tlie carrier lifetime. 

Most of the AHoy 600 outer diameter tube corrosion has occurred in the region of the upper tubesheet near the open lane, ie, an untubed lane across the middle of the steam generator (16,17). The steam carries entrained droplets of water through the open lane to the upper tubesheet region where the droplets dry out and concentrate the chemicals. Long tube inserts have been used to sleeve tubes in this region where wall defects have been detected. 

In short, the abolition of privity opened manufacturers to HabiUty for negligence. Plaintiffs, however, could not estabUsh claims merely by proving that they were harmed by defective products from a manufacturer. The requirement that classic fault be estabUshed often stood as a formal barrier to a successhil tort action. 

Arrhythmias. The first solution to cardiovascular problems arising from arrhythmias came about as a result of a complication caused by open-heart surgery. During procedures to correct congenital defects in children s hearts, the electrical conduction system often became impaired, and until it healed, the heart could not contract sufficiently without outside electrical stimulation. A system that plugged into a wall outlet was considered adequate until an electrical storm knocked out power, lea ding to the development of the first battery-powered external pacemaker. 

Weld-seam defects. Failure to fuse the metal fully along the weld line in welded tubes may result in a linear open seam or crevice. 

Surface defects, if sufficiently severe, may result in failure by themselves. More commonly, they act as triggering mechanisms for other failure modes. For example, open laps or seams may lead to crevice corrosion or to concentration sites for ions that may induce stress-corrosion cracking. 

An important eomponent in the lube oil system is the aeeumulator. It must be periodieally eheeked for proper eharge and bladder or diaphragm integrity. This ean be done at any time. With bladder-type aeeumulators, elose aeeumulator bloek valve, open drain valves, and observe the eharge pressure. If there is no pressure, eharge the bladder to the speeified pressure. If pressure cannot be maintained, the bladder is defective and must be changed. 

The submitters employed alcohol-free potassium ferf-butoxide, purchased from K K Laboratories, without further purification the checkers employed comparable material taken from a freshly opened bottle purchased from MSA Research Corporation. The submitters report that among approximately ten different bottles of commercial potassium terf-butoxide used, only material from one bottle failed to form the tricarbonate in this procedure. The defective material in this one bottle was an extremely fine powder that failed to dissolve when... 

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